2015-2016 USGS/FEMA Lidar: Connecticut River Watershed, NH
Data Set (DS) | OCM Partners (OCMP)GUID: gov.noaa.nmfs.inport:71770 | Updated: January 2, 2024 | Published / External
Summary
Short Citation
OCM Partners, 2024: 2015-2016 USGS/FEMA Lidar: Connecticut River Watershed, NH, https://www.fisheries.noaa.gov/inport/item/71770.
Full Citation Examples
Geographic Extent: Connecticut River Watershed (4,437 sq mi), Winnipesaukee River Watershed (796 sq mi), and portions of the White Mountain National Forest (WMNF) in New Hampshire (181 sq mi), covering approximately 5,233 total square miles.
Dataset Description: The Connecticut River Watershed 2015 project called for the planning, acquisition, processing and derivative products of LIDAR data to be collected at an aggregate nominal pulse spacing (NPS) of 0.7 meters the Connecticut and Winnipesaukee River Watershed areas of interest, and 0.58 meters NPS for the White Mountain National Forest project area. Project specifications are based on the U.S. Geological Survey National Geospatial Program Base Lidar Specification, Version 1.2 as well as the National Enhanced Elevation Assessment (NEEA) for QL2/QL2+ data for the WMNF area. The data was developed based on a horizontal projection/datum of NAD83 (2011) State Plane New Hampshire, US survey feet and vertical datum of NAVD88 (Geoid 12B), US survey feet. Lidar data for all three areas of interest was delivered in RAW LAS 1.4 flightline swath format, and processed to create Classified LAS 1.4 Files formatted to 6,464 individual 5,000-foot x 5,000-foot tiles.
After approval of the initial dataset was received from the USGS, the additional deliverables was produced for the White Mountain National Forest project area. This dataset includes tiled classified LAS data (first and last return) in LAS 1.4 and comma-delimited ASCII formats and 2.5-foot bare-earth raster DEMs in Esri grid format. Tiles names follow the naming schema implemented in previous WMNF task orders.
Data were subsequently reprocessed to Entwine Point Tile (EPT) format in web mercator projection with vertical meters. The EPT form of the data is used by the NOAA Digital Coast Data Access Viewer, which this metadata record is supporting. Additional processing steps may have been done by the Data Access Viewer and will be recorded in the lineage section.
Ground Conditions: LiDAR collection began in Fall 2015, while no snow was on the ground and rivers were at or below normal levels. In order to post process the LiDAR data to meet task order specifications, Quantum Spatial established 155 calibration control points in order to calibrate the LIDAR to known ground locations established throughout the project area. The accuracy of the data was checked with 135 NVA points and 117 VVA points (252 total QC checkpoints).
Distribution Information
-
Not Applicable
Create custom data files by choosing data area, product type, map projection, file format, datum, etc. A new metadata will be produced to reflect your request using this record as a base. Change to an orthometric vertical datum is one of the many options.
None
Users should be aware that temporal changes may have occurred since this data set was collected and some parts of this data may no longer represent actual surface conditions. Users should not use this data for critical applications without a full awareness of its limitations.
Controlled Theme Keywords
COASTAL ELEVATION, elevation, TERRAIN ELEVATION
Child Items
No Child Items for this record.
Contact Information
Point of Contact
NOAA Office for Coastal Management (NOAA/OCM)
coastal.info@noaa.gov
(843) 740-1202
https://coast.noaa.gov
Metadata Contact
NOAA Office for Coastal Management (NOAA/OCM)
coastal.info@noaa.gov
(843) 740-1202
https://coast.noaa.gov
Extents
-72.57793839123° W,
-70.9282606398° E,
45.3113522389° N,
42.70426337249° S
2015-10-24 - 2016-04-29
Item Identification
Title: | 2015-2016 USGS/FEMA Lidar: Connecticut River Watershed, NH |
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Short Name: | 2015-2016 CT River NH m10025 |
Status: | Completed |
Publication Date: | 2016 |
Abstract: |
Geographic Extent: Connecticut River Watershed (4,437 sq mi), Winnipesaukee River Watershed (796 sq mi), and portions of the White Mountain National Forest (WMNF) in New Hampshire (181 sq mi), covering approximately 5,233 total square miles. Dataset Description: The Connecticut River Watershed 2015 project called for the planning, acquisition, processing and derivative products of LIDAR data to be collected at an aggregate nominal pulse spacing (NPS) of 0.7 meters the Connecticut and Winnipesaukee River Watershed areas of interest, and 0.58 meters NPS for the White Mountain National Forest project area. Project specifications are based on the U.S. Geological Survey National Geospatial Program Base Lidar Specification, Version 1.2 as well as the National Enhanced Elevation Assessment (NEEA) for QL2/QL2+ data for the WMNF area. The data was developed based on a horizontal projection/datum of NAD83 (2011) State Plane New Hampshire, US survey feet and vertical datum of NAVD88 (Geoid 12B), US survey feet. Lidar data for all three areas of interest was delivered in RAW LAS 1.4 flightline swath format, and processed to create Classified LAS 1.4 Files formatted to 6,464 individual 5,000-foot x 5,000-foot tiles. After approval of the initial dataset was received from the USGS, the additional deliverables was produced for the White Mountain National Forest project area. This dataset includes tiled classified LAS data (first and last return) in LAS 1.4 and comma-delimited ASCII formats and 2.5-foot bare-earth raster DEMs in Esri grid format. Tiles names follow the naming schema implemented in previous WMNF task orders. Data were subsequently reprocessed to Entwine Point Tile (EPT) format in web mercator projection with vertical meters. The EPT form of the data is used by the NOAA Digital Coast Data Access Viewer, which this metadata record is supporting. Additional processing steps may have been done by the Data Access Viewer and will be recorded in the lineage section. Ground Conditions: LiDAR collection began in Fall 2015, while no snow was on the ground and rivers were at or below normal levels. In order to post process the LiDAR data to meet task order specifications, Quantum Spatial established 155 calibration control points in order to calibrate the LIDAR to known ground locations established throughout the project area. The accuracy of the data was checked with 135 NVA points and 117 VVA points (252 total QC checkpoints). |
Purpose: |
Classified LAS files are used to show the manually reviewed bare earth surface. This allows the user to create breaklines, raster DEMs, and intensity images. The purpose of these lidar data was to produce high accuracy 3D hydro-flattened digital elevation models (DEM) and intensity images with a 2.5-foot cell size. These raw lidar point cloud data were used to create classified lidar LAS files, 3D breaklines, hydro-flattened DEMs, and intensity images as necessary. |
Supplemental Information: |
USGS Contract: G10PC00026 Task Order Number: G15PD00886 CONTRACTOR: Quantum Spatial Lidar data calibrated by Quantum Spatial, Inc. with data acquired by QSI, Woolpert, Inc., and PAR. All follow-on processing was completed by the prime contractor.
The following are the USGS lidar fields in JSON: {
"ldrinfo" : {
"ldrspec" : "USGS-NGP Base Specification v1.2", "ldrsens" : "Leica ALS 70", "ldrmaxnr" : "4", "ldrnps" : "0.69", "ldrdens" : "2.12", "ldranps" : "0.69", "ldradens" : "2.12", "ldrfltht" : "2075", "ldrfltsp" : "160", "ldrscana" : "40.0", "ldrscanr" : "40.7", "ldrpulsr" : "264.0", "ldrpulsd" : "4", "ldrpulsw" : "0.47", "ldrwavel" : "1064", "ldrmpia" : "1", "ldrbmdiv" : "0.22", "ldrswatw" : "1510.48", "ldrswato" : "13.11", "ldrgeoid" : "g2012bu0.bin" }, "ldrinfo_Concord" : {
"ldrspec" : "USGS-NGP Base Specification v1.2", "ldrsens" : "Leica ALS 70", "ldrmaxnr" : "4", "ldrnps" : "0.69", "ldrdens" : "2.12", "ldranps" : "0.69", "ldradens" : "2.12", "ldrfltht" : "2075", "ldrfltsp" : "160", "ldrscana" : "40.0", "ldrscanr" : "40.7", "ldrpulsr" : "264.0", "ldrpulsd" : "4", "ldrpulsw" : "0.47", "ldrwavel" : "1064", "ldrmpia" : "1", "ldrbmdiv" : "0.22", "ldrswatw" : "1510.48", "ldrswato" : "12.70", "ldrgeoid" : "g2012bu0.bin" }, "ldrinfo_Keene" : {
"ldrspec" : "USGS-NGP Base Specification v1.2", "ldrsens" : "Leica ALS 70", "ldrmaxnr" : "4", "ldrnps" : "0.69", "ldrdens" : "2.12", "ldranps" : "0.69", "ldradens" : "2.12", "ldrfltht" : "2075", "ldrfltsp" : "160", "ldrscana" : "40.0", "ldrscanr" : "40.7", "ldrpulsr" : "264.0", "ldrpulsd" : "4", "ldrpulsw" : "0.47", "ldrwavel" : "1064", "ldrmpia" : "1", "ldrbmdiv" : "0.22", "ldrswatw" : "1510.48", "ldrswato" : "13.23", "ldrgeoid" : "g2012bu0.bin" }, "ldrinfo_Lebanon" : {
"ldrspec" : "USGS-NGP Base Specification v1.2", "ldrsens" : "Leica ALS 70", "ldrmaxnr" : "4", "ldrnps" : "0.69", "ldrdens" : "2.12", "ldranps" : "0.69", "ldradens" : "2.12", "ldrfltht" : "2075", "ldrfltsp" : "160", "ldrscana" : "40.0", "ldrscanr" : "40.7", "ldrpulsr" : "264.0", "ldrpulsd" : "4", "ldrpulsw" : "0.47", "ldrwavel" : "1064", "ldrmpia" : "1", "ldrbmdiv" : "0.22", "ldrswatw" : "1510.48", "ldrswato" : "13.25", "ldrgeoid" : "g2012bu0.bin" }, "ldrinfo_Pittsburg" : {
"ldrspec" : "USGS-NGP Base Specification v1.2", "ldrsens" : "Leica ALS 70", "ldrmaxnr" : "4", "ldrnps" : "0.69", "ldrdens" : "2.12", "ldranps" : "0.69", "ldradens" : "2.12", "ldrfltht" : "2075", "ldrfltsp" : "160", "ldrscana" : "40.0", "ldrscanr" : "40.7", "ldrpulsr" : "264.0", "ldrpulsd" : "4", "ldrpulsw" : "0.47", "ldrwavel" : "1064", "ldrmpia" : "1", "ldrbmdiv" : "0.22", "ldrswatw" : "1510.48", "ldrswato" : "13.54", "ldrgeoid" : "g2012bu0.bin" }, "ldrinfo_StJohnsburyNorth" : {
"ldrspec" : "USGS-NGP Base Specification v1.2", "ldrsens" : "Leica ALS 70", "ldrmaxnr" : "4", "ldrnps" : "0.69", "ldrdens" : "2.12", "ldranps" : "0.69", "ldradens" : "2.12", "ldrfltht" : "2075", "ldrfltsp" : "160", "ldrscana" : "40.0", "ldrscanr" : "40.7", "ldrpulsr" : "264.0", "ldrpulsd" : "4", "ldrpulsw" : "0.47", "ldrwavel" : "1064", "ldrmpia" : "1", "ldrbmdiv" : "0.22", "ldrswatw" : "1510.48", "ldrswato" : "12.68", "ldrgeoid" : "g2012bu0.bin" }, "ldrinfo_StJohnsburySouth" : {
"ldrspec" : "USGS-NGP Base Specification v1.2", "ldrsens" : "Leica ALS 70", "ldrmaxnr" : "4", "ldrnps" : "0.69", "ldrdens" : "2.12", "ldranps" : "0.69", "ldradens" : "2.12", "ldrfltht" : "2075", "ldrfltsp" : "160", "ldrscana" : "40.0", "ldrscanr" : "40.7", "ldrpulsr" : "264.0", "ldrpulsd" : "4", "ldrpulsw" : "0.47", "ldrwavel" : "1064", "ldrmpia" : "1", "ldrbmdiv" : "0.22", "ldrswatw" : "1510.48", "ldrswato" : "12.17", "ldrgeoid" : "g2012bu0.bin" }, "ldrinfo_Winnepesaukee" : {
"ldrspec" : "USGS-NGP Base Specification v1.2", "ldrsens" : "Leica ALS 70", "ldrmaxnr" : "4", "ldrnps" : "0.69", "ldrdens" : "2.12", "ldranps" : "0.69", "ldradens" : "2.12", "ldrfltht" : "2075", "ldrfltsp" : "160", "ldrscana" : "40.0", "ldrscanr" : "40.7", "ldrpulsr" : "264.0", "ldrpulsd" : "4", "ldrpulsw" : "0.47", "ldrwavel" : "1064", "ldrmpia" : "1", "ldrbmdiv" : "0.22", "ldrswatw" : "1510.48", "ldrswato" : "12.82", "ldrgeoid" : "g2012bu0.bin" }, "ldrinfo_WMNF" : {
"ldrspec" : "USGS-NGP Base Specification v1.2", "ldrsens" : "Leica ALS 70", "ldrmaxnr" : "4", "ldrnps" : "0.56", "ldrdens" : "3.21", "ldranps" : "0.56", "ldradens" : "3.21", "ldrfltht" : "160", "ldrfltsp" : "160", "ldrscana" : "28.0", "ldrscanr" : "49.6", "ldrpulsr" : "273.0", "ldrpulsd" : "4", "ldrpulsw" : "0.047", "ldrwavel" : "1064", "ldrmpia" : "1", "ldrbmdiv" : "0.22", "ldrswatw" : "1034.71", "ldrswato" : "19.98", "ldrgeoid" : "g2012bu0.bin" }, "ldraccur" : {
"ldrchacc" : "0.196", "rawnva" : "0.093", "rawnvan" : "133", "clsnva" : "0.092", "clsnvan" : "134", "clsvva" : "0.284", "clsvvan" : "116" }, "lasinfo" : {
"lasver" : "1.4", "lasprf" : "6", "laswheld" : "Withheld (ignore) points were identified in these files using the standard LAS Withheld bit", "lasolap" : "Swath "overage" points were identified in these files using the standard LAS overlap bit", "lasintr" : "16", "lasclass" : {
"clascode" : "1", "clasitem" : "Processed, but unclassified" }, "lasclass" : {
"clascode" : "2", "clasitem" : "Bare-earth ground" }, "lasclass" : {
"clascode" : "7", "clasitem" : "Low noise" }, "lasclass" : {
"clascode" : "9", "clasitem" : "Water" }, "lasclass" : {
"clascode" : "10", "clasitem" : "Ignored Ground" }, "lasclass" : {
"clascode" : "17", "clasitem" : "Bridge Decks" }, "lasclass" : {
"clascode" : "18", "clasitem" : "High noise" } }} |
Keywords
Theme Keywords
Thesaurus | Keyword |
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Global Change Master Directory (GCMD) Science Keywords |
EARTH SCIENCE > LAND SURFACE > TOPOGRAPHY > TERRAIN ELEVATION
|
Global Change Master Directory (GCMD) Science Keywords |
EARTH SCIENCE > OCEANS > COASTAL PROCESSES > COASTAL ELEVATION
|
ISO 19115 Topic Category |
elevation
|
Spatial Keywords
Thesaurus | Keyword |
---|---|
Global Change Master Directory (GCMD) Location Keywords |
CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA
|
Global Change Master Directory (GCMD) Location Keywords |
CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > NEW HAMPSHIRE
|
Global Change Master Directory (GCMD) Location Keywords |
VERTICAL LOCATION > LAND SURFACE
|
Instrument Keywords
Thesaurus | Keyword |
---|---|
Global Change Master Directory (GCMD) Instrument Keywords |
LIDAR > Light Detection and Ranging
|
Platform Keywords
Thesaurus | Keyword |
---|---|
Global Change Master Directory (GCMD) Platform Keywords |
Airplane > Airplane
|
Physical Location
Organization: | Office for Coastal Management |
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City: | Charleston |
State/Province: | SC |
Data Set Information
Data Set Scope Code: | Data Set |
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Data Set Type: | Elevation |
Maintenance Frequency: | None Planned |
Data Presentation Form: | Model (digital) |
Distribution Liability: |
Any conclusions drawn from the analysis of this information are not the responsibility of NOAA, the Office for Coastal Management or its partners |
Data Set Credit: | USGS; FEMA; Quantum Spatial |
Support Roles
Data Steward
Date Effective From: | 2024 |
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Date Effective To: | |
Contact (Organization): | NOAA Office for Coastal Management (NOAA/OCM) |
Address: |
2234 South Hobson Ave Charleston, SC 29405-2413 |
Email Address: | coastal.info@noaa.gov |
Phone: | (843) 740-1202 |
URL: | https://coast.noaa.gov |
Distributor
Date Effective From: | 2024 |
---|---|
Date Effective To: | |
Contact (Organization): | NOAA Office for Coastal Management (NOAA/OCM) |
Address: |
2234 South Hobson Ave Charleston, SC 29405-2413 |
Email Address: | coastal.info@noaa.gov |
Phone: | (843) 740-1202 |
URL: | https://coast.noaa.gov |
Metadata Contact
Date Effective From: | 2024 |
---|---|
Date Effective To: | |
Contact (Organization): | NOAA Office for Coastal Management (NOAA/OCM) |
Address: |
2234 South Hobson Ave Charleston, SC 29405-2413 |
Email Address: | coastal.info@noaa.gov |
Phone: | (843) 740-1202 |
URL: | https://coast.noaa.gov |
Point of Contact
Date Effective From: | 2024 |
---|---|
Date Effective To: | |
Contact (Organization): | NOAA Office for Coastal Management (NOAA/OCM) |
Address: |
2234 South Hobson Ave Charleston, SC 29405-2413 |
Email Address: | coastal.info@noaa.gov |
Phone: | (843) 740-1202 |
URL: | https://coast.noaa.gov |
Extents
Currentness Reference: | Ground Condition |
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Extent Group 1
Extent Group 1 / Geographic Area 1
W° Bound: | -72.57793839123 | |
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E° Bound: | -70.9282606398 | |
N° Bound: | 45.3113522389 | |
S° Bound: | 42.70426337249 |
Extent Group 1 / Time Frame 1
Time Frame Type: | Range |
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Start: | 2015-10-24 |
End: | 2016-04-29 |
Spatial Information
Spatial Resolution
Horizontal Distance: | 0.6 Meter |
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Spatial Representation
Representations Used
Grid: | No |
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Vector: | Yes |
Text / Table: | No |
TIN: | No |
Stereo Model: | No |
Video: | No |
Vector Representation 1
Point Object Present?: | Yes |
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Point Object Count: | 97194025751 |
Reference Systems
Reference System 1
Coordinate Reference System |
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Reference System 2
Coordinate Reference System |
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Access Information
Security Class: | Unclassified |
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Data Access Procedure: |
Data is available online for bulk or custom downloads |
Data Access Constraints: |
None |
Data Use Constraints: |
Users should be aware that temporal changes may have occurred since this data set was collected and some parts of this data may no longer represent actual surface conditions. Users should not use this data for critical applications without a full awareness of its limitations. |
Distribution Information
Distribution 1
Start Date: | 2024-01-02 |
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End Date: | Present |
Download URL: | https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=10025/details/10025 |
Distributor: | NOAA Office for Coastal Management (NOAA/OCM) (2024 - Present) |
File Name: | Customized Download |
Description: |
Create custom data files by choosing data area, product type, map projection, file format, datum, etc. A new metadata will be produced to reflect your request using this record as a base. Change to an orthometric vertical datum is one of the many options. |
Distribution Format: | Not Applicable |
Compression: | Zip |
URLs
URL 1
URL: | https://coast.noaa.gov/dataviewer/ |
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Name: | NOAA's Office for Coastal Management (OCM) Data Access Viewer (DAV) |
URL Type: |
Online Resource
|
File Resource Format: | HTML |
Description: |
The Data Access Viewer (DAV) allows a user to search for and download elevation, imagery, and land cover data for the coastal U.S. and its territories. The data, hosted by the NOAA Office for Coastal Management, can be customized and requested for free download through a checkout interface. An email provides a link to the customized data, while the original data set is available through a link within the viewer. |
Technical Environment
Description: |
MicroStation Version 8; TerraScan Version 15; TerraModeler Version 15; GeoCue Version 2014.1.21.4; ESRI ArcGIS 10.3; Global Mapper 16; Leica Cloud Pro 1.2; Windows 7 Operating System \\PSIHQ_NX3200\Projects\Projects\26818_CT_River_Watershed_Winnipesaukee 597 GB and \\matrix\matrix\LIDAR\26818_CT_River 11.9 TB |
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Data Quality
Vertical Positional Accuracy: |
Quantitative values: 0.093 m, 0.092 m, and 0.284 m. Tests that produced these values: The raw NVA was tested using 133 independent survey points located in open terrain. The surveyed checkpoints were distributed throughout the project area and surveyed using GNSS procedures and methodologies that provide reliable and consistent results to meet the project's accuracy requirements. Please see the "Survey Accuracy Requirements" and "Field Methodology" sections in the Survey Report for more information. Elevations from the unclassified lidar surface were measured for the x,y location of each check point. Elevations interpolated from the unclassified lidar surface were then compared to the elevation values of the surveyed control. The RMSEz was computed to be 0.047 meters and AccuracyZ to be 0.093 meters. This meets the required AccuracyZ value of 0.196 meters raw NVA at 95 percent confidence level using (RMSEz * 1.9600) as defined by the National Standards for Spatial Data Accuracy (NSSDA); assessed and reported using National Digital Elevation Program (NDEP)/ASPRS Guidelines.
The NVA was tested using 134 independent survey points located in open terrain. The surveyed checkpoints were distributed throughout the project area and surveyed using GNSS procedures and methodologies that provide reliable and consistent results to meet the project's accuracy requirements. Please see the "Survey Accuracy Requirements" and "Field Methodology" sections in the Survey Report for more information. Elevations from the DEM surface were measured for the x,y location of each check point. Elevations interpolated from the DEM surface were then compared to the elevation values of the surveyed control. The RMSEz was computed to be 0.047 meters and AccuracyZ to be 0.092 meters. This meets the required AccuracyZ value of 0.196 meters NVA at 95 percent confidence level using (RMSEz * 1.9600) as defined by the National Standards for Spatial Data Accuracy (NSSDA); assessed and reported using National Digital Elevation Program (NDEP)/ASPRS Guidelines.
The VVA was tested using 116 independent survey points located in vegetated terrain. The surveyed checkpoints were distributed throughout the project area and surveyed using GNSS procedures and methodologies that provide reliable and consistent results to meet the project's accuracy requirements. Please see the "Survey Accuracy Requirements" and "Field Methodology" sections in the Survey Report for more information. Elevations from the DEM surface were measured for the x,y location of each check point. Elevations interpolated from the DEM surface were then compared to the elevation values of the surveyed control. The VVA was computed to be 0.284 meters. This meets the required value of 0.294 meters VVA at 95th percentile level using the 95th percentile of the absolute value of all vertical errors in all combined vegetation classes as defined by the National Standards for Spatial Data Accuracy (NSSDA); assessed and reported using National Digital Elevation Program (NDEP)/ASPRS Guidelines. |
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Completeness Report: |
These raw LAS data files include all data points collected. No points have been removed or excluded. A visual qualitative assessment was performed to ensure data completeness. No void areas or missing data exist. The raw point cloud is of good quality and data passes Nonvegetated Vertical Accuracy specifications. |
Conceptual Consistency: |
Data cover the entire area specified for this project. |
Data Management
Have Resources for Management of these Data Been Identified?: | Yes |
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Approximate Percentage of Budget for these Data Devoted to Data Management: | Unknown |
Do these Data Comply with the Data Access Directive?: | Yes |
Actual or Planned Long-Term Data Archive Location: | NCEI-NC |
How Will the Data Be Protected from Accidental or Malicious Modification or Deletion Prior to Receipt by the Archive?: |
Data is backed up to cloud storage. |
Lineage
Sources
Entwine Point Tiles
Contact Role Type: | Publisher |
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Contact Type: | Organization |
Contact Name: | USGS |
Citation URL: | https://s3-us-west-2.amazonaws.com/usgs-lidar-public/USGS_LPC_CT_River_Lot6_Winnipesaulee_2015_LAS_2017/ept.json |
Citation URL Name: | Entwine Point Tiles |
Citation URL Description: |
Entwine Point Tiles for Connecticut River Watershed 2015-2016 lidar data, New Hampshire. |
Source Contribution: |
Data referenced by the Digital Coast Data Access Viewer. |
Process Steps
Process Step 1
Description: |
Lidar Pre-Processing: Airborne GPS and IMU data were merged to develop a Single Best Estimate (SBET) of the lidar system trajectory for each lift. Lidar ranging data were initially calibrated using previous best parameters for this instrument and aircraft. Relative calibration was evaluated using advanced plane-matching analysis and parameter corrections derived. This was repeated iteratively until residual errors between overlapping swaths, across all project lifts, was reduced to acceptable levels. Data were then block adjusted to match surveyed calibration control. Raw data NVA were checked using independently surveyed checkpoints. Swath overage points were identified and tagged within each swath file. The results of the final calibration, NVA and horizontal accuracy assessments, and the "raw" swaths were forwarded to the client to obtain a Notice To Proceed on classification and derivative product generation. |
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Process Date/Time: | 2016-01-01 00:00:00 |
Process Step 2
Description: |
Lidar Post-Processing: The calibrated and controlled lidar swaths were processed using automatic point classification routines in proprietary software. These routines operate against the entire collection (all swaths, all lifts), eliminating character differences between files. Data were then distributed as virtual tiles to experienced lidar analysts for localized automatic classification, manual editing, and peer-based QC checks. Supervisory QC monitoring of work in progress and completed editing ensured consistency of classification character and adherence to project requirements across the entire project area. All classification tags are stored in the original swath files. After completion of classification and final QC approval, the NVA and VVA for the project are calculated. Sample areas for each land cover type present in the project area were extracted and forwarded to the client, along with the results of the accuracy tests. Upon acceptance, the complete classified lidar swath files were delivered to the client. |
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Process Date/Time: | 2016-01-01 00:00:00 |
Process Step 3
Description: |
Classified LAS Processing: The bare earth surface is then manually reviewed to ensure correct classification on the Class 2 (Ground) points. After the bare-earth surface is finalized, it is then used to generate all hydro-breaklines through heads-up digitization. All ground (ASPRS Class 2) LiDAR data inside of the Lake Pond and Double Line Drain hydro flattening breaklines were then classified to water (ASPRS Class 9) using TerraScan macro functionality. A buffer of 1 meter was also used around each hydro-flattened feature to classify these ground (ASPRS Class 2) points to Ignored ground (ASPRS Class 10). All Lake Pond Island and Double Line Drain Island features were checked to ensure that the ground (ASPRS Class 2) points were reclassified to the correct classification after the automated classification was completed. All bridge decks were classified to Class 17. All overlap data was processed through automated functionality provided by TerraScan to classify the overlapping flight line data to approved classes by USGS. The overlap data was identified using the Overlap Flag, per LAS 1.4 specifications. All data was manually reviewed and any remaining artifacts removed using functionality provided by TerraScan and TerraModeler. Global Mapper us used as a final check of the bare earth dataset. GeoCue was then used to create the deliverable industry-standard LAS files for both the All Point Cloud Data and the Bare Earth. Quantum Spatial proprietary software was used to perform final statistical analysis of the classes in the LAS files, on a per tile level to verify final classification metrics and full LAS header information. |
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Process Date/Time: | 2016-01-01 00:00:00 |
Process Step 4
Description: |
Data were converted to Entwine Point Tiles (EPT) in Web Mercator projection and units of meters by USGS. NOAA is leveraging the EPT files for use in the Digital Coast Data Access Viewer and created this metadata to support that usage. |
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Process Contact: | NOAA Office for Coastal Management (NOAA/OCM) |
Phone (Voice): | (843) 740-1202 |
Email Address: | coastal.info@noaa.gov |
Source: | Entwine Point Tiles |
Catalog Details
Catalog Item ID: | 71770 |
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GUID: | gov.noaa.nmfs.inport:71770 |
Metadata Record Created By: | Kirk Waters |
Metadata Record Created: | 2024-01-02 12:45+0000 |
Metadata Record Last Modified By: | Kirk Waters |
Metadata Record Last Modified: | 2024-01-02 13:05+0000 |
Metadata Record Published: | 2024-01-02 |
Owner Org: | OCMP |
Metadata Publication Status: | Published Externally |
Do Not Publish?: | N |
Metadata Last Review Date: | 2024-01-02 |
Metadata Review Frequency: | 3 Years |
Metadata Next Review Date: | 2027-01-02 |